The 1.6 8-valver, which measures are worthwhile? (268°, 4-2-1, exhaust)

Discussion in '8-valve' started by WAUOla, May 21, 2019.

  1. WAUOla Forum Member

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    Okay, I find some old threads via Google, but not when searching in here, forcing me to start a brand new thread.

    My starting point is an old 1.6 'EZ', originally supplied in my 1985 mk2. I'm interested in what you others in here give as cues for improvements, primary focus is what the Germans write as "Motorelastizität" - improved driveability for street (and potentially a one off trackday).

    • Increasing displacement/stroke:
      I plan to bolt in a 1.8 'RP' (and 4+E gearbox), seeing both 'RP' and 'EZ' are stated as having a C/R of 9.0:1, because that is what at hand from a very cost effective purchase.
    • Exhaust: Jetex 2" resonnated ordered. Is there anything to it, sourcing i.e. GTI 8V manifold and downpipe, or is it 4-1 or 4-2-1 sooner than later due cost/effect?
    • Head work:
      Seeing the 'EZ' is a 2E2 header, and the 'RP' a monojetronic (SPI), I guess both headers can be utilized for my purpose (cam will be changed). Am I right, reprofiling valves, new valve guides, bigger inlet valves and mild porting makes sense?
      (I read in here comments on 'EZ' being closer to 8.2:1, allowing for skimming 1-2mm of head deck)
    • Camshaft: for my purpose, I am considering something alike Schrick 268 or Techtonics 270 degree camshaft.
    • Carburettor: my 2E2 has actually been holding up well. Will it need any special attention, being refitted onto a 1.8L bottom-end?
     
  2. Tristan

    Tristan Paid Member Paid Member

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    Is there a reason for not just fitting a gti engine?
     
  3. HPR

    HPR Administrator Admin

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    From the point of view of drivability, have good low rpm Torque and allow more breath at say 5000 upwards to have a bit more topend … a 1.8 which can be made nearer 1.9 going up in bore from 81 > to 82.5 - 83 mm
    or even fit a 2.0 unit.... but maybe thats overkill or you like things period correct or dont want to touch the bottom end ...and mainly focus on cilinderhead, inlet, exhaust and C.R


    - Headwork : This is key to get nice gains…due a better breathing engine
    light porting with focus,that inlet ports and inlet manifold line up nice to avoid mismatch
    and mainly open up the valveseats and bowl under the valve…. as here will be the largest restriction.
    On ports i would not go much bigger, just focus on nice radius transitions….
    Also rework the valves as that also brings a little extra flow


    - Compression ratio @ 9 / 1 sound a bit low to me... think around 10/ 1 , as its on a carb and its a streetcar

    - The std cam is about 258- 260 @ 0,1 mm / 220 degr @ 1.0 mm and 10.2mm valvelift ( afaik )
    with pretty low compression its key to keep duration pretty short
    so upgrade to say a 268 cam is wise … so that will be about 228 degr @ 1.0 mm and a little extra lift

    - Eventually advance the cam a couple degrees…
     
    Last edited: May 22, 2019
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  4. rubjonny

    rubjonny Administrator Staff Member Admin

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    a 1.8 carb engine GU and the MK1 equivalent EX cylinder block is the same as the GTI EV, DX, 2H, PB etc and will give you the 10-1 compression. You could keep your old head or use the 1.8 carb/spi head, or even a GTI head if you like which is slightly better as standard. though if you want to keep the 2e2 carb make sure its a digifant type head then you can drill a hole for the inlet manifold coolant channel the 2e2 needs for its autochoke and waxstat to work properly. If you use the RP I'm not sure if they have the coolant channel in the inlet, or if the head can be drilled to suit the 2e2 carb though I guess it can.

    go for the GTI 4-2-1 OEM manifold and downpipe for sure, it flows better than the carb style toilet bowl. I did this on my 1.6 carb and that mod alone made it rev much more freely so I recommend it for sure.

    if you install a kjet 8v distributor this will also help as the ignition curve is that much better than the carb setup, again this mod alone on a friends 1.8 carb engine really perked it up.

    having said all the above to keep the 2e2 happy, once you start tuning the engine you may find the 2e2 cant keep up with it and tuning supplies/advice for these units are harder to come by than say the good old fashioned weber conversion which is much more widely supported. the 2e2 carb was used on 1.8 units though so you could start with 1.8 jets and see how it works for you. I guess they can be drilled out too but I havent looked into that side of things
     
  5. WAUOla Forum Member

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    Is simply because this is a tuck-away-car, and I like the -somewhat- idea of sticking with its origin. Going from a 1.6 to 1.8 is the same block etc, so no MOT issues to be expected. I guess I just like the idea of classic tuning, so a matter of taste. (I fully understand the argument of bang for the buck, going engine change, and IF I'd ever do that, I think it would have to be getting a 16V again and put all the badges from my old KR on.) Then again, if I need to have a serious street condender, you see, I will only step into the other classic being parked. :)

    There is also somewhat of an interest, seeing how enhancements are percieved on a 2-valver: there is also an Audi 100 10V we're considering to give a mild go, and there's also rebuilding an old Group B prototype engine (2-valve extreme).

    Thank you HPR, for a well written response!

    I do get the impression I'm not too far off with my ideas, even though I do not plan a bottom-end enhancement just yet. If so, I think doing bore and pistons for a 1.9 on a bit higher compression makes sense. But for now, please let's focus on the more basic options for bolt-ons and header tweaks; I guess good examples of the porting can be found on the sticky thread of Mr Hillclimber. Do you have any assumptions on where the driveable powerband will be on the 268 cam - if improving slightly on the lower end, and keeping breath better up until 5500-6000 area, that sounds like good option, in case a 272 gets a bit too uncivilized.

    And regarding inlet valves. Did I understand you correct, in sticking with the 38mm ones (low comb standards) as upgrading to 40mms isn't worth it in the scale of this project?
     
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  6. Jon Olds Forum Junkie

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    I run an 1600 EZ on std carb in my road CITI and realise the choke size is small so chasing high rpm gains is fairly pointless.
    Just happened to have a 2L head lying around so its cam has gone in (+1mm lift) while I replaced the hyd buckets
    Jon
     
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  7. HPR

    HPR Administrator Admin

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    Indeed , your idea on mods is inline with what i would do...to get a balanced system

    If performance is the main consideration i would go for a 272 ( or + ) cam but i had the same idea that it would/may be a bit too uncivilised…. ( altough the step is not that big )
    so opted for the 268 cam and to get an engine which has good torque low down.... and it will have enough punch to rev when asked… ( its something you need to decide what is acceptable ..)

    I dont expect that you will see the powerband shift much upwards with the 268 cam
    and as the breathing will be better with headwork, inlet and axhaust... i expect the plateau ( curve ) will lift pretty much over the full range

    On valve size, i wasnt sure it had 40 mm valves or not….
    Going from 38 to 40 mm is about 10% more valve area ( valve troath / inside seat @ 90 % of valve diameter )
    So thats a nice gain to have
    BUT considered that power output will be moderate... and its not meant to sqeeze the last drop out... then may stay with 38 mm valves


    http://www.catcams.com/engines/camshaft-setup.aspx
     
    Last edited: May 22, 2019
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  8. Jon Olds Forum Junkie

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    With HPR on valve size, stay 38mm, I've had a very well flowing head with 38mm inlets in the past
    Jon
     
  9. WAUOla Forum Member

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    I've been in touch with this guy before, regarding a 10V refinement (due >300 000km driven), and thought I'd check up on his work and suggestions about this idea of a build too. You can see he's work on a GTI header here: https://www.ebbt.no/vw-18-gti-toppbygg/

    A cam can be retrofitted quite easily, but doing the dirty work on a header is more ideal to priortizie now I suppose. And if the carb is getting exchanged at some point, holding back at 38mm inlets doesn't make sense, does it?
     
  10. HPR

    HPR Administrator Admin

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    Volkswagen went also bigger valves … so it wont hurt…
    Altough, a proper ported head with 38 mm valves probably flow more than a std head /mild ported head with 40 mm valves….
     
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  11. WAUOla Forum Member

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    I was quoted approx 600 GBP for work by this EBB-fella:
    skim it down approx 1mm (roughly 1mm = +1 in C/R), mild porting, guides being broched, new washers, clean up the OE valves and recut, recut valve seats.

    For inlet valves, I'd say optimizing stock 38mm, replace with 7mm stemmed 38mm or 7mm stemmed 40mm inlets are the options to go.
    Reason is simply, that a hydraulic head needs valves that differs from the OE GTIs anyhow due overall height.

    I can bolt on the exhaust, leave it be. I can fetch the "universal" bolt on cam-train. I can go the distance with the craftsmanship...but it's clear dropping in GTI 8V or GTI 16V hardware is far less expensive indeed.

    @Jon Olds care to share about the 38mm setup you ran, what the idea was and what you managed with it?
     
  12. Jon Olds Forum Junkie

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    It was a pro 1870cc rally motor that I bought ran rebuilt and sold on. Very sweet engine, way quicker than the spec would suggest. That wasapprox 15-20 years ago (Terry 47 may be able to comment more)
    Jon
     
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  13. Jon Olds Forum Junkie

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    Usual rally spec, solid lifter, twin 45's etc. And 'only' 38mm inlet valves
    Jon
     
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  14. WAUOla Forum Member

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    Seeking some inspiration here and there, I made a loot to youtube. Not too many good videos of type 268 camshafts, but I was later on recommended a mk2 GTI at the 'ring. I commented the guy, asking a bit on his thoughts on having the 268 on a 8V. Then I figured out it was @copeidge I was writing to!

    How do you consider the lobe separation? Am I right in understanding the high(er) compression GTI engine will tackle the dBilas/Newman 268s with the 110 LSA fairly well on idle, but the low compressions will not and are more suited for Schrick/RSR 268s with the 113 LSA ? How is the LSA affecting the mid and high range (110 vs 113 LSA) ?
     
  15. HPR

    HPR Administrator Admin

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    OEM cams are mostly in the 110 - 114 LSA range …
    To say that one cam idles better than the other on low vs high compression ratio … imo there wont be much difference on a mild cam as a 268,
    altough the 113 LSA has a bit less overlap....
    ( I reckon minimum 9 or 9.5/1 when we talk about low C.R on a Atmo engine )
     
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  16. WAUOla Forum Member

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    Price request sent RSR performance for their - seemingly bang-for-the-buch - offering on a Schrick duplicate 268/113/11,2mm item.
    Any reason to look for INA lightweight followers on such a mild cam?
     
  17. Jon Olds Forum Junkie

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    I have a spare schrick 268, pm me
    Jon
     
  18. WAUOla Forum Member

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    Seeing my starting point has a set back in CR, I suppose anything over 272 degrees makes no sense.
    I'm a bit baffled about all the different 8V cams in the range of (266-)268-272, but there are many potential candidates. Majority seems to run either 11,2 or 11,4mm lift = better low end torque. The LSA though, I cannot figure out holds any significance as you say, but all are in the range of 110-113.

    Doppel-wobber holds some interesting comments on low-CR 8V camshafting:
    "Sportnockenwelle 266°/Nothelle/VW Classic: Ebenfalls noch problemlos fahrbar im PN, EZ und RP, guter Leerlauf bei 900 U/min und gerade noch AU tauglich beim PN und RP Motor. Deutliche Mehrleistung und sattes Drehmoment ab 2000 U/min beim PN/EZ. Spürbare Mehrleistung und Drehmomentsteigerung beim RP Motor. Verdichtungserhöhung bei diesen drei Motoren auf min. 10:1 empfehlenswert. Beim PF Motor geringe Mehrleistung spürbar und ab 1500 U/min spürbar mehr Drehmoment...AU Tauglich.


    Sportnockenwelle 268° dbilas: Rauher und unsauberer Leerlauf bei PN und EZ, nicht mehr unbedingt zu empfehlen, beim RP Motor noch gerade akzeptabel. Gute Mehrleistung und spürbar mehr Drehmoment beim RP sowie gute Drehfreude bis über 6000 U/min.


    Beim PF Leerlauf wie Serie bei 850-900 U/min ( sauberes einmessen beim Einbau vorrausgesetzt ), kleine Korrekturen an CO-Schraube/LMM und Leerlaufeinstellschraube nötig. Spürbare Mehrleistung und sattes Drehmoment ab 1800 U/min bis 5200 U/min... AU Tauglich. Verdichtungserhöhung auf min. 10,5:1 empfohlen. Bei Sportnockenwellen ab 268° sind Fächerkrümmer ( 4-2-1 ), Sportkatalysator und 55mm Sport-AGA samt Zylinderkopfbearbeitung und Verdichtungserhöhung auf min. 10,5:1 empfehlenswert ! Einspritzdüsen mit ca. 10% mehr Durchfluss ( vom OPEL oder BMW ) werden empfohlen. Verstellbares NW-Rad ebenfalls empfehlenswert.


    Sportnockenwelle 270°/Autotech USA: Nur noch für Mehrfacheinspritzmotoren empfehlenswert wie PF oder GX. Bei sorgfältigem einmessen Leerlauf bei 900 U/min, Korrekturen an CO/LMM und Leerlaufschraube nötig...AU Tauglich. Gute Mehrleistung und deutliche Drehmomentsteigerung ab 2000 U/min bis über 6000 U/min mit schöner, homogener Leistungskurve ( ähnlich einem TD-Motor ). Verdichtungserhöhung auf 11:1 nötig sowie weitere Tuningmaßnahmen wie Fächerkrümmer, Sportkat, 55mm Sport-AGA, Zylinderkopfbearbeitung, usw um in den vollen Genuß dieser Sportnocke zu kommen. Verstellbares NW-Rad und E-Düsen mit mehr Durchsatz empfohlen.
    "

    Then I got a friend to look up the classic dictionary of Gert Hack:

    "ABT
    Golf II, Jett II, Passat 35i (MKB: RP 66 kW/90 PS): Umbau auf ca. 87 kW/106 PS
    ABT-Hochleistungsnockenwelel, Verdichtungsanhebung, Anpassung der Einspritzanlage, Anpassung der Zündung, Anpassung der Abgasanlage (Krümmer und Hosenrorh), Optimierung der Luftführung, Beschleunigung ca 10,7 sec (Golf). Drehmoment ca. 152 Nm bei 3900 U/min.

    Dennert
    Golf II, Jetta II, 1,6 l, 75 PS – Umbau auf ca. 73 kW / 100 PS
    Bearbeiteter Zylinderkopf, Ein- und Auslasskanäle erweitert und geglättet, Ventile bearbeitet. Ansaug- und Auspuffkrümmer den erweiterten Kanälen angepasst. Erhöhung der Verdichtung. Nockenwelle mit geänderten Steuerzeiten under grösserem Ventilhub. Vergaserbestückung angepasst. Zündkerzen mit höherem Wärmewert. Drehmoment: 148 Nm bei 4000 U/min.

    Golf II, Jetta II, 1,8 l, 90 PS Vergaser – Umbau auf ca. 82 kW / 112 PS
    Bearbeiteter Zylinderkopf, Ein- und Auslasskanäle erweitert und geglättet, Ventile bearbeitet. Ansaug- und Auspuffkrümmer den erweiterten Kanälen angepasst. Erhöhung der Verdichtung. Nockenwelle mit geänderten Steuerzeiten under grösserem Ventilhub. Vergaserbestückung angepasst. Zündkerzen mit höherem Wärmewert. Drehmoment: 160 Nm bei 3500 U/min.


    Golf II, Jetta II, 90 PS Monojetronic Kat– Umbau auf ca. 79 kW / 107 PS
    Bearbeiteter Zylinderkopf, Ein- und Auslasskanäle erweitert und geglättet, Ventile bearbeitet. Ansaug- und Auspuffkrümmer den erweiterten Kanälen angepasst. Erhöhung der Verdichtung. Nockenwelle mit geänderten Steuerzeiten under grösserem Ventilhub. Vergaserbestückung angepasst. Zündkerzen mit höherem Wärmewert. Drehmoment: 159 Nm bei 3250 U/min.


    Hartmann
    Golf II 66 kW / 90 PS + 15 kW / 20 PS
    HM-BiKat-Fächerkrümmer und HM-Auspuffanlage der Phase 3 bringen zusammen mit einer spezielle abgestimmten HM-Nockenwelle eine deutliche Erhöhung der Spitzenleistung, des Drehmoments sowie der Drehfreudigkeit. Weiterhin bleifrei Benzin.

    Veytal

    Golf II 90 PS / 66 kW + 16 PS / 11,8 kW
    Fächerkrümmer und Sport-Auspuffanlage mit Spezial Nockenwelle 272 * Steigerung des Drehmoments und Spitzenleistung. Bleifrei Super.


    Oettinger
    Motor 1800 VN
    Konstruktiver Änderungen gegenüber 1,6 Liter/75 PS und 1,5 Liter/70 PS: 1,8 Liter Kurbelwelle (Hubraum total: 1796 cm3), Satz Mulden-Kolben 79,5 mm Ø (Verdichtung 8,4 : 1), Zylinderkopt-Bearbeitung, grössere Einlass-Ventile (40 mm) und Auslass-Ventile (34 mm), Zenith-Vergaser 2-B-2, Ansaugsrohr-Bearbeitung.
    Leistung: 81 kW (110 PS) bei 5500/min
    "
     
  19. HPR

    HPR Administrator Admin

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    As driveablility, good idle and feel cultivated with some extra punch is the target, i would go short duration 266 -268 or even a std cam… but to make a good judgement we need to see what the base spec is...
    I guess its close to 260 degree and good 10 mm lift... and Mech or Hydro ?

    Given that C.R is pretty low i would stay pretty close to std cam duration but with some extra lift.... and the wider LSA for less overlap

    We also talked about head porting and even bigger valves …. maybe even with a std cam
    ( and a few degrees advanced which helps low end grunt.. )
    and extra compression make things more forgiving with more duration / overlap
     
  20. WAUOla Forum Member

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    I suspect 268 would be the best option to cover (transitionally) a setup with and without a compression-increase.
    Thus, I'm giving the dBilas 268 a go now, even if 110 in LSA, as it has the 11,4mm lift which seems more desireable (compared to Schrick 268/113/11,2mm).

    @Jon Olds I double checked with dBilas, regarding the 110 LSA, if they recommended it also for low CR engines, and they did. Fingers crossed.
     
    Last edited: Jul 5, 2019

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